{
  "bibcode": "2022GCN.31874....1P",
  "body": "D. M. Palmer (LANL), S. D. Barthelmy (GSFC), R. Caputo (GSFC),\nH. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa),\nC. B. Markwardt (GSFC), T. Parsotan (GSFC/UMBC),\nT. Sakamoto (AGU), M. Stamatikos (OSU)\n(i.e. the Swift-BAT team):\n  \nUsing the data set from T-119 to T+183 sec from the recent telemetry downlink,\nwe report further analysis of BAT GRB 220408A (trigger #1101675)\n(Caputo, et al., GCN Circ. 31848).  The BAT ground-calculated position is\nRA, Dec = 202.399, 47.065 deg which is\n    RA(J2000)  =  13h 29m 35.7s\n    Dec(J2000) = +47d 03' 55.4\"\nwith an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 34%.\n  \nThe mask-weighted light curve shows a multi-peaked structure that\nstarts at T-2 s and peaks at T+3 s.  There is a weak emission which\npeaks at T+17 s.  T90 (15-350 keV) is 17.25 +- 1.10 sec\n(estimated error including systematics).\n  \nThe time-averaged spectrum from T-0.55 to T+18.26 sec is best fit by a power law\nwith an exponential cutoff.  This fit gives a photon index 1.19 +- 0.57,\nand Epeak of 35.3 +- 8.8 keV (chi squared 62.40 for 56 d.o.f.).  For this\nmodel the total fluence in the 15-150 keV band is 1.2 +- 0.1 x 10^-6 erg/cm2\nand the 1-sec peak flux measured from T+2.48 sec in the 15-150 keV band is\n4.9 +- 0.4 ph/cm2/sec.  A fit to a simple power law gives a photon index\nof 2.14 +- 0.13 (chi squared 72.77 for 57 d.o.f.).  All the quoted errors\nare at the 90% confidence level.\n  \nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/1101675/BA/",
  "circularId": 31874,
  "createdOn": 1649680465000,
  "email": "tsakamoto@phys.aoyama.ac.jp",
  "subject": "GRB 220408A: Swift-BAT refined analysis",
  "submitter": "Takanori Sakamoto at AGU  <tsakamoto@phys.aoyama.ac.jp>",
  "eventId": "GRB 220408A"
}